CHAP. 23.—ELECTRUM.

In all[1] gold ore there is some silver, in varying proportions; a tenth part in some instances, an eighth in others. In one mine, and that only, the one known as the mine of Albucrara, in Gallæcia,[2] the proportion of silver is but one thirty-sixth: hence it is that the ore of this mine is so much more valuable than that of others. Whenever the proportion of silver is one-fifth, the ore is known also by the name of "electrum;"[3] grains, too, of this metal are often found in the gold known as "canaliense."[4] An artificial[5] electrum, too, is made, by mixing silver with gold. If the proportion of silver exceeds one-fifth, the metal offers no resistance on the anvil.

Electrum, too, was highly esteemed in ancient times, as we learn from the testimony of Homer, who represents[6] the palace of Menelaüs as refulgent with gold and electrum, silver and ivory. At Lindos, in the island of Rhodes, there is a temple dedicated to Minerva, in which there is a goblet of electrum, consecrated by Helena: history states also that it was moulded after the proportions of her bosom. One peculiar advantage of electrum is, its superior brilliancy to silver by lamp-light. Native electrum has also the property of detecting poisons; for in such case, semicircles, resembling the rainbow in appearance, will form upon the surface of the goblet, and emit a crackling noise, like that of flame, thus giving a twofold indication of the presence of poison.[7]

1. This is almost, but not quite, universally the case.

2. In Spain. See B. iii. c. 4, B. iv. c. 34, and B. ix. c. 2. The locality alluded to is now unknown.

3. A name also given by the ancients to amber. Artificial "electrum," or gold alloyed with silver, was known in the most ancient times.

4. The gold found by sinking shafts. See Chapter 21.

5. See B. ix. c. 65.

6. Od. B. iv. 1. 71.

7. Pliny no doubt has been imposed upon in this instance.